Java tutorial
/* This file is part of the iText (R) project. Copyright (c) 1998-2016 iText Group NV Authors: Bruno Lowagie, Paulo Soares, et al. This program is free software; you can redistribute it and/or modify it under the terms of the GNU Affero General Public License version 3 as published by the Free Software Foundation with the addition of the following permission added to Section 15 as permitted in Section 7(a): FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program; if not, see http://www.gnu.org/licenses or write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA, 02110-1301 USA, or download the license from the following URL: http://itextpdf.com/terms-of-use/ The interactive user interfaces in modified source and object code versions of this program must display Appropriate Legal Notices, as required under Section 5 of the GNU Affero General Public License. In accordance with Section 7(b) of the GNU Affero General Public License, a covered work must retain the producer line in every PDF that is created or manipulated using iText. You can be released from the requirements of the license by purchasing a commercial license. Buying such a license is mandatory as soon as you develop commercial activities involving the iText software without disclosing the source code of your own applications. These activities include: offering paid services to customers as an ASP, serving PDFs on the fly in a web application, shipping iText with a closed source product. For more information, please contact iText Software Corp. at this address: sales@itextpdf.com */ package com.itextpdf.signatures; import com.itextpdf.io.codec.Base64; import com.itextpdf.kernel.PdfException; import com.itextpdf.kernel.pdf.PdfEncryption; import java.io.BufferedOutputStream; import java.io.ByteArrayInputStream; import java.io.DataOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.math.BigInteger; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.nio.charset.StandardCharsets; import java.security.GeneralSecurityException; import java.security.KeyStore; import java.security.KeyStoreException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.Signature; import java.security.cert.CRL; import java.security.cert.CRLException; import java.security.cert.Certificate; import java.security.cert.CertificateEncodingException; import java.security.cert.CertificateException; import java.security.cert.CertificateFactory; import java.security.cert.CertificateParsingException; import java.security.cert.X509Certificate; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Calendar; import java.util.Collection; import java.util.Date; import java.util.Enumeration; import java.util.GregorianCalendar; import java.util.Iterator; import java.util.List; import java.util.NoSuchElementException; import org.bouncycastle.asn1.ASN1ObjectIdentifier; import org.bouncycastle.asn1.ASN1Sequence; import org.bouncycastle.asn1.DERNull; import org.bouncycastle.asn1.DEROctetString; import org.bouncycastle.asn1.esf.SigPolicyQualifierInfo; import org.bouncycastle.asn1.esf.SigPolicyQualifiers; import org.bouncycastle.asn1.ocsp.OCSPObjectIdentifiers; import org.bouncycastle.asn1.x509.AlgorithmIdentifier; import org.bouncycastle.asn1.x509.Extension; import org.bouncycastle.asn1.x509.Extensions; import org.bouncycastle.cert.X509CertificateHolder; import org.bouncycastle.cert.jcajce.JcaX509CertificateConverter; import org.bouncycastle.cert.jcajce.JcaX509CertificateHolder; import org.bouncycastle.cert.ocsp.BasicOCSPResp; import org.bouncycastle.cert.ocsp.CertificateID; import org.bouncycastle.cert.ocsp.OCSPException; import org.bouncycastle.cert.ocsp.OCSPReq; import org.bouncycastle.cert.ocsp.OCSPReqBuilder; import org.bouncycastle.cms.jcajce.JcaSimpleSignerInfoVerifierBuilder; import org.bouncycastle.jce.X509Principal; import org.bouncycastle.jce.provider.X509CertParser; import org.bouncycastle.operator.OperatorCreationException; import org.bouncycastle.operator.bc.BcDigestCalculatorProvider; import org.bouncycastle.operator.jcajce.JcaContentVerifierProviderBuilder; import org.bouncycastle.operator.jcajce.JcaDigestCalculatorProviderBuilder; import org.bouncycastle.tsp.TSPException; import org.bouncycastle.tsp.TimeStampToken; import org.bouncycastle.x509.util.StreamParsingException; class SignUtils { static final Object UNDEFINED_TIMESTAMP_DATE = null; static CRL parseCrlFromStream(InputStream input) throws CertificateException, CRLException { return CertificateFactory.getInstance("X.509").generateCRL(input); } static byte[] getExtensionValueByOid(X509Certificate certificate, String oid) { return certificate.getExtensionValue(oid); } static MessageDigest getMessageDigest(String hashAlgorithm) throws GeneralSecurityException { return new BouncyCastleDigest().getMessageDigest(hashAlgorithm); } static MessageDigest getMessageDigest(String hashAlgorithm, IExternalDigest externalDigest) throws GeneralSecurityException { return externalDigest.getMessageDigest(hashAlgorithm); } static MessageDigest getMessageDigest(String hashAlgorithm, String provider) throws NoSuchAlgorithmException, NoSuchProviderException { if (provider == null || provider.startsWith("SunPKCS11") || provider.startsWith("SunMSCAPI")) { return MessageDigest.getInstance(DigestAlgorithms.normalizeDigestName(hashAlgorithm)); } else { return MessageDigest.getInstance(hashAlgorithm, provider); } } static InputStream getHttpResponse(URL urlt) throws IOException { HttpURLConnection con = (HttpURLConnection) urlt.openConnection(); if (con.getResponseCode() / 100 != 2) { throw new PdfException(PdfException.InvalidHttpResponse1).setMessageParams(con.getResponseCode()); } return (InputStream) con.getContent(); } static CertificateID generateCertificateId(X509Certificate issuerCert, BigInteger serialNumber, AlgorithmIdentifier digestAlgorithmIdentifier) throws OperatorCreationException, CertificateEncodingException, OCSPException { return new CertificateID(new JcaDigestCalculatorProviderBuilder().build().get(digestAlgorithmIdentifier), new JcaX509CertificateHolder(issuerCert), serialNumber); } static CertificateID generateCertificateId(X509Certificate issuerCert, BigInteger serialNumber, ASN1ObjectIdentifier identifier) throws OperatorCreationException, CertificateEncodingException, OCSPException { return new CertificateID( new JcaDigestCalculatorProviderBuilder().build() .get(new AlgorithmIdentifier(identifier, DERNull.INSTANCE)), new JcaX509CertificateHolder(issuerCert), serialNumber); } static OCSPReq generateOcspRequestWithNonce(CertificateID id) throws IOException, OCSPException { OCSPReqBuilder gen = new OCSPReqBuilder(); gen.addRequest(id); Extension ext = new Extension(OCSPObjectIdentifiers.id_pkix_ocsp_nonce, false, new DEROctetString(new DEROctetString(PdfEncryption.generateNewDocumentId()).getEncoded())); gen.setRequestExtensions(new Extensions(new Extension[] { ext })); return gen.build(); } static InputStream getHttpResponseForOcspRequest(byte[] request, URL urlt) throws IOException { HttpURLConnection con = (HttpURLConnection) urlt.openConnection(); con.setRequestProperty("Content-Type", "application/ocsp-request"); con.setRequestProperty("Accept", "application/ocsp-response"); con.setDoOutput(true); OutputStream out = con.getOutputStream(); DataOutputStream dataOut = new DataOutputStream(new BufferedOutputStream(out)); dataOut.write(request); dataOut.flush(); dataOut.close(); if (con.getResponseCode() / 100 != 2) { throw new PdfException(PdfException.InvalidHttpResponse1).setMessageParams(con.getResponseCode()); } //Get Response return (InputStream) con.getContent(); } static boolean isSignatureValid(BasicOCSPResp validator, Certificate certStoreX509, String provider) throws OperatorCreationException, OCSPException { if (provider == null) provider = "BC"; return validator.isSignatureValid( new JcaContentVerifierProviderBuilder().setProvider(provider).build(certStoreX509.getPublicKey())); } static void isSignatureValid(TimeStampToken validator, X509Certificate certStoreX509, String provider) throws OperatorCreationException, TSPException { if (provider == null) provider = "BC"; validator.validate(new JcaSimpleSignerInfoVerifierBuilder().setProvider(provider).build(certStoreX509)); } static boolean checkIfIssuersMatch(CertificateID certID, X509Certificate issuerCert) throws CertificateEncodingException, IOException, OCSPException { return certID.matchesIssuer(new X509CertificateHolder(issuerCert.getEncoded()), new BcDigestCalculatorProvider()); } static Date add180Sec(Date date) { return new Date(date.getTime() + 180000L); } static Iterable<X509Certificate> getCertsFromOcspResponse(BasicOCSPResp ocspResp) { List<X509Certificate> certs = new ArrayList<>(); X509CertificateHolder[] certHolders = ocspResp.getCerts(); JcaX509CertificateConverter converter = new JcaX509CertificateConverter(); for (X509CertificateHolder certHolder : certHolders) { try { certs.add(converter.getCertificate(certHolder)); } catch (Exception ex) { } } return certs; } static Collection<Certificate> readAllCerts(byte[] contentsKey) throws StreamParsingException { X509CertParser cr = new X509CertParser(); cr.engineInit(new ByteArrayInputStream(contentsKey)); return cr.engineReadAll(); } static <T> T getFirstElement(Iterable<T> iterable) { return iterable.iterator().next(); } static X509Principal getIssuerX509Name(ASN1Sequence issuerAndSerialNumber) throws IOException { return new X509Principal(issuerAndSerialNumber.getObjectAt(0).toASN1Primitive().getEncoded()); } public static String dateToString(Calendar signDate) { return new SimpleDateFormat("yyyy.MM.dd HH:mm:ss z").format(signDate.getTime()); } static class TsaResponse { String encoding; InputStream tsaResponseStream; } static TsaResponse getTsaResponseForUserRequest(String tsaUrl, byte[] requestBytes, String tsaUsername, String tsaPassword) throws IOException { URL url = new URL(tsaUrl); URLConnection tsaConnection; try { tsaConnection = url.openConnection(); } catch (IOException ioe) { throw new PdfException(PdfException.FailedToGetTsaResponseFrom1).setMessageParams(tsaUrl); } tsaConnection.setDoInput(true); tsaConnection.setDoOutput(true); tsaConnection.setUseCaches(false); tsaConnection.setRequestProperty("Content-Type", "application/timestamp-query"); //tsaConnection.setRequestProperty("Content-Transfer-Encoding", "base64"); tsaConnection.setRequestProperty("Content-Transfer-Encoding", "binary"); if ((tsaUsername != null) && !tsaUsername.equals("")) { String userPassword = tsaUsername + ":" + tsaPassword; tsaConnection.setRequestProperty("Authorization", "Basic " + Base64.encodeBytes(userPassword.getBytes(StandardCharsets.UTF_8), Base64.DONT_BREAK_LINES)); } OutputStream out = tsaConnection.getOutputStream(); out.write(requestBytes); out.close(); TsaResponse response = new TsaResponse(); response.tsaResponseStream = tsaConnection.getInputStream(); response.encoding = tsaConnection.getContentEncoding(); return response; } static boolean hasUnsupportedCriticalExtension(X509Certificate cert) { if (cert.hasUnsupportedCriticalExtension()) { for (String oid : cert.getCriticalExtensionOIDs()) { // KEY USAGE and DIGITAL SIGNING is ALLOWED if ("2.5.29.15".equals(oid) && cert.getKeyUsage()[0]) { continue; } try { // EXTENDED KEY USAGE and TIMESTAMPING is ALLOWED if ("2.5.29.37".equals(oid) && cert.getExtendedKeyUsage().contains("1.3.6.1.5.5.7.3.8")) { continue; } } catch (CertificateParsingException e) { // DO NOTHING; } return true; } } return false; } static Calendar getTimeStampDate(TimeStampToken timeStampToken) { GregorianCalendar calendar = new GregorianCalendar(); calendar.setTime(timeStampToken.getTimeStampInfo().getGenTime()); return calendar; } static Signature getSignatureHelper(String algorithm, String provider) throws NoSuchProviderException, NoSuchAlgorithmException { return provider == null ? Signature.getInstance(algorithm) : Signature.getInstance(algorithm, provider); } static SigPolicyQualifiers createSigPolicyQualifiers(SigPolicyQualifierInfo... sigPolicyQualifierInfo) { return new SigPolicyQualifiers(sigPolicyQualifierInfo); } static Iterable<X509Certificate> getCertificates(final KeyStore keyStore) throws KeyStoreException { final Enumeration<String> keyStoreAliases = keyStore.aliases(); return new Iterable<X509Certificate>() { @Override public Iterator<X509Certificate> iterator() { return new Iterator<X509Certificate>() { private X509Certificate nextCert; @Override public boolean hasNext() { if (nextCert == null) { tryToGetNextCertificate(); } return nextCert != null; } @Override public X509Certificate next() { if (!hasNext()) { throw new NoSuchElementException(); } X509Certificate cert = nextCert; nextCert = null; return cert; } private void tryToGetNextCertificate() { while (keyStoreAliases.hasMoreElements()) { try { String alias = keyStoreAliases.nextElement(); if (keyStore.isCertificateEntry(alias)) { nextCert = (X509Certificate) keyStore.getCertificate(alias); break; } } catch (KeyStoreException e) { continue; } } } @Override public void remove() { throw new UnsupportedOperationException("remove"); } }; } }; } }